class TravelApprovalQuery:
    def __init__(self, travel_approval_id=None, travel_id=None, manager_id=None, date=None):
        self.travel_approval_id = travel_approval_id
        self.travel_id = travel_id
        self.manager_id = manager_id
        self.date = date

    def to_dict(self):
        return {
            "travel_approval_id": self.travel_approval_id,
            "travel_id": self.travel_id,
            "manager_id": self.manager_id,
            "date": self.date.isoformat() if self.date else None
        }
